During questioning at an Independent Commission Against Corruption inquiry, Mr Obeid denied that the lies were deliberately aimed at concealing the Obeid family's involvement in a mining tenement that resources minister Ian Macdonald is alleged to have drawn up for the benefit of the Obeids.

Paul Obeid admitted that his family had tried to enter into mining joint ventures with several resources companies, before Mr Macdonald called for companies to seek exploration licences.

However, Paul Obeid denied that Mr Macdonald had created the tenement that covered the Obeids' properties especially for them.

Geoffrey Watson SC, asked: "And it was done with a view to enabling you and your family to profit on Cherrydale Park [the Obeid farm at Bylong]?"

He also said he hadn't lied, but rather had been inaccurate, at a private hearing by the Independent Commission Against Corruption in August 2012.

On that occasion, Paul Obeid was asked whether he had told the people at Cascade Coal whether the Obeids were behind a company called Buffalo Resources.

At the time, the Obeids were using a "front" company to negotiate a stake in Cascade Coal, which had won the government tender to explore for coal where the Obeids had bought up crucial farms.

"Certainly, they knew they were dealing with Obeids," said Paul Obeid on that occasion.

Paul Obeid tried to distance himself from that response, saying his evidence was inaccurate and that he was under pressure.

Several members of the Cascade syndicate have claimed they were not aware that the Obeid family were behind a deal which resulted in the Obeids getting a 25 per cent stake in Cascade Coal. Cascade director John McGuigan has told the inquiry he knew that the Obeids were involved.

The family later sold their share for $30 million, with the promise of a further $30 million, which the Obeids are currently demanding Cascade pay them.

Using the three properties they acquired in advance of the 2008 government tender, the Obeids also have an agreement whereby Cascade will buy the three properties for four times their value if a mine eventuates. This will net the Obeids a further $20 million.

There have been a number of testy exchanges between Commissioner David Ipp and Graham Turnbull, SC, who is representing four Obeid sons: Damian, Paul, Eddie jnr and Gerard.

After patching up their differences, Commissioner Ipp quipped that perhaps the pair needed to see a marriage guidance counsellor.

The commission will not sit on Friday this week, meaning star witness Mr Macdonald will now appear on Monday.